LOS ANGELES — The California Highway Patrol faulted a semi-truck driver Friday for a fiery head-on collision with a bus that killed 10, but officials said they still don't know why his big rig veered across an interstate median and into oncoming traffic, killing five high school students on their way to visit a college and a couple who had just gotten engaged.
The underlying cause of the crash is the FedEx semi-truck driver, Tim Evans, 32, "allowing his vehicle to travel across the median in an unsafe turning movement," Sgt. Nathan Parsons said. "He could have fell asleep, he could have had an undiagnosed medical condition. We're unable to prove either."
The April 10, 2014, collision occurred in Orland, about 100 miles north of Sacramento. The dead were five high school students from the Los Angeles area, three chaperones, and the drivers of the FedEx tractor-trailer and the bus. The bus was full of prospective Humboldt State University students heading for a campus visit, and two of the chaperones had been planning their wedding.
The California Highway Patrol released the results of its investigation at a news conference after the agency met with family members of those killed in the collision.
The agency was unable to find any mechanical defects with any vehicles involved in the crash.
The agency said driver fatigue could have played a factor, but it could not conclude either way if that or a medical condition played any role in the crash because Evans' body was so badly burned.
Evans "had sufficient time off," Parsons said. "That day, he had been working approximately eight hours at the time of the collision. But he had between eight and 10 hours of sleep the night before."
Evans was survived by a wife, who did not immediately return a Facebook message on Friday.
Carla Haywood, whose daughter Mattison died on the bus, said the investigation still didn't address their central question of why the truck driver left the road. "We're constantly wondering what happened, questioning what could have been prevented," said Haywood, 63, of Chino.
Mattison, 25, and her fiancÃ©, 29-year-old Michael Myvett, who also died in the crash, were chaperones on the trip and had just gotten engaged in Paris. It was their second year together accompanying students on a campus trip designed to encourage the enrollment of students with disadvantaged backgrounds who would have been the first in their families to attend college.
Michael Myvett's grandmother, Debra Loyd, said the investigation's conclusion has given her closure.
"It was the driver's fault," said Loyd, 63, of Los Angeles. "I'm satisfied. For one year, we didn't know anything. Now we know something."
She called on FedEx to settle lawsuits stemming from the crash and award damages to survivors and the families of those who were killed.
"C'mon, FedEx. Get it done," she said. "Do what you gotta do. It's time."
FedEx is reviewing the report and will not comment until the National Transportation Safety Board finishes its separate investigation, company spokesman Jim McCluskey said. Victims and their families also are suing the bus company, Silverado Stages.
Gaylord Hill, whose now-19-year-old son survived the crash, said he wasn't satisfied with the investigation because without a definitive cause, nothing can be done to prevent a similar crash.
He said he thought the California Highway Patrol did all it could.
"They did the best they could," Hill said. "There was an explosion and a fire, and all the evidence burned up."
Ever since the crash, it has been unclear why the FedEx semi gradually veered across the interstate median and into oncoming traffic. Investigators found no evidence that Evans attempted to slow down or swerve before the crash.
The National Transportation Safety Board released documents earlier this month showing Evans had no drugs or alcohol in his system and was reportedly in good health.
Those records also included uncorroborated witness accounts offering possible insight into the investigation. One passenger seated three rows behind the bus driver said he saw Evans with his head down and slumped toward the door immediately before the crash. Another driver on the highway said the semi's left-turn signal lit up before it changed lanes and drifted across the median.
A couple in a sedan sideswiped by the truck before the crash reported seeing flames coming out of one of its trailers, but state and federal investigators found no physical evidence to support that statement.
The National Transportation Safety Board could release its final report this summer, an agency spokesman said last week.
Nirappil reported from Sacramento.